1. Field of the Invention
The present invention relates to a heat transfer recording method for recording images on a recording medium and, and a heat transfer recording apparatus using such method. More particularly, it relates to a heat transfer recording method for recording images on a recording medium by transferring ink from a transfer medium including the ink to the recording medium, and a heat transfer recording apparatus for carrying out such method.
The heat transfer recording apparatus can include electronic typewriters, word processors, printers, copying machines, facsimiles and the like.
2. Related Background Art
Up to date, various recording apparatuses have been developed as output means for outputting the inputted information. Among them, a typical one is a heat transfer recording apparatus.
In the heat transfer recording apparatus, an image is recorded on a recording paper by pressing an ink sheet against the recording paper by a recording head, then by selectively heating the recording head to fuse heat fusible ink coated on the ink sheet in accordance with an image pattern, thus transferring the fused ink onto the recording paper. Accordingly, the heat transfer recording apparatus has advantages that it is light-weighted, compact and noiseless, and, therefore, has been widely used as the output means of word processors, electronic typewriters and the like.
In the heat transfer recording apparatus, while it is preferable to use the recording paper having smooth surfaces such as a plain paper, it has recently been requested to record the image even on a rough (smoothless) recording paper such as a bond paper, as well as the smooth-faced plain paper, with high dignity.
In order to record the image on the rough recording paper with high dignity, it is desirable to increase the pressing force of the recording head acting on the recording paper. However, if the pressing force of the recording head is increased, when the smooth-faced plain paper is used as the recording paper, it will be difficult to correct the image erroneously recorded on the plain paper; thus, it is necessary to make the pressing force variable. In this case, however, when the pressing force of the recording head is increased in case of the rough recording paper, the moving ink sheet will slip on the recording paper and/or there will be a delay in separation of the ink sheet from the recording paper, thus worsening the dignity of the recorded image.
In this way, in the conventional heat transfer recording method, there will be a difference in dignity of the recorded image in accordance with the degree of smoothness of the used recording papers. In particular, when the smoothless recording paper such as a rough paper is used, the edge of the image transferred to and recorded on such smoothless paper will be indistinct or blurred, and, further, if the ink is heat transferable ink including wax as a main component, the image recorded on the smoothless paper will be light in color.
It has been tried to increase the density of the transferred image by using the heat transferable ink including, as a main component, resin having relatively high viscosity when fused. However, in this case, since the ink is extensible, the edge of the transferred image will be indistinct (i.e., the sharpness of the edge of the recorded image will be insufficient), thereby worsening the dignity of the image.